David Jameson

University of Hawaii

Department of Cell and Molecular Biology

Recent Research Projects

1) Conformational dynamics of ribosomal proteins: both prokaryotic and eukaryotic “stalk” proteins

Using time-resolved and steady-state approaches we have demonstrated that the stalk protein L7/L12 is highly flexible and that rapid subunit exchange can occur between dimers in solution.

Recent work with Pierre Moens using FRET have also addressed the solution structure of L7/L12

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Using FCS methods (in collaboration with the LFD) we have also carried out studies on the distribution of eukaryotic stalk proteins among ribosome populations in vivo

The next crucial step would be to study the protein associated with intact ribosomes during various stages of the protein biosynthesis process.

(B) Homogeneous distribution: all ribosomes carry one monomer of the four proteins.

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2) The large GTPase dynamin:

We have studied – in vitro – the self-association of the dynamin, specifically using ultracentrifugation we demonstrated a monomer-tetramer equilibrium.

The next step would be to study the self-association and membrane association of dynamin in vivo using GFP constructs

We have also studied dynmain binding to Giant Unilamellar Vesicles

Major Instrumentation

ISS PC photon-counting spectrofluorimeterSteady-state fluorescence/polarization

ISS K2 multifrequency phase and modulation fluorometerTime-resolved fluorescence/time-decay anisotropy

Hi-Tech stopped flow spectrofluorimeterRapid kinetics